1. Technical Field
Embodiments of the inventive concept relate to a power converting apparatus which operates in a two-phase mode, and in particular to a power converting apparatus characterized by a shape of a core made of a magnetic material.
2. Description of the Related Art
Conventionally, in an electronic equipment product such as video and audio equipment or office automation (OA) information equipment, a circuit adopting a two-phase interleave system is known.
As one example, the circuit adopting a two-phase interleave system includes a plurality of boosting circuits connected in parallel to a DC current, each boosting circuit being composed of a boosting choke, a boosting diode, and a switching element. For example, technology related to a power converting apparatus operating in a two-phase mode where a smoothing capacitor is connected to an output side of the boosting circuit has been proposed. In addition, one approach includes connecting a load in parallel with the smoothing capacitor. Each switching element configuring a boosting circuit to be subjected to pulse-width modulation control by a control signal pulse supplied from a control circuit, or the like, has also been proposed.
Further, as one example of the shape of a core made of a magnetic material, a technology using an EC core has been proposed. For example, in a power converting apparatus, which operates in a two-phase mode, a shape of an EC core is produced by forming two E-shaped magnetic flux material portions (hereinafter called “E-shaped core members”), which can include c-shaped magnetic flux material portions (e.g., 20a, 20b, 20c, and 20d, hereinafter, called “c-shaped core members”), as shown in FIG. 1. The two E-shaped magnetic flux material portions are prepared to mutually face each other and can be coupled together. Surrounding the peripheries of the two E-shaped magnetic flux material portions are large C-shaped magnetic flux material parts (e.g., 25, hereinafter called “C-shaped core members”). In other words, the E-shaped core members and the C-shaped core members are combined to form the EC core.
In the EC core, however, gaps G such as shown in FIG. 1 are necessarily formed. Due to the gaps G, problems related to power loss of magnetic flux loss occurs. In the industry, in an apparatus using a power converting apparatus (e.g., such as a DC/DC converter, an inverter circuit, or the like), which are used in vehicles (e.g., hybrid vehicles, a product provided with a power motor, a heavy-duty construction site vehicle, a bulldozer, a loading shovel, a robot, or other electric equipments, or the like), there is a strong demand to reduce the size of the on-board power converting apparatus.
Further, since the above-described EC core is a core produced by combining the c-shaped core members 20a through 20d and surrounding the peripheries of the combined c-shaped core members 20a through 20d by the large C-shaped core members 25, a ratio of a sectional area Y1 of a central leg of the core, a sectional area Y2 of an outside leg Y2 (e.g, right side) of the core, and a sectional area Y3 of an outside leg (e.g., left side) of the core is 1:1:1, as shown in FIG. 2. Therefore, in such an EC core as described in FIG. 2, there is a problem in that the sectional areas of both the outside legs are excessively large, which cannot adapt to a demand for size reduction.
Therefore, in an apparatus using such a power converting apparatus, development of a power converting apparatus, which is compact and operates with reduced power loss would be desirable.
In view of these circumstances, it would be desirable to provide a power converting apparatus, which reduces power loss, has a small occupation area, is reduced in size, and has a core shape in which the manufacturing process is simplified.